June 7, 1861, was appointed by the governor of Ohio major of the Twenty-third Ohio Volunteers. September 19, 1861, was appointed by General Rosecrans judge-advocate of the Department of the Ohio. October 24, 1861, was promoted to the rank of lieutenant-colonel. In the battle of South Mountain, September 14, 1862, distinguished himself by gallant conduct in leading a charge and in holding a position at the head of his troops after being severely wounded in his left arm. October 24, 1862, was appointed colonel of the Twenty-third Ohio. In July, 1863, while with the army in southwestern Virginia, caused an expedition of two regiments and a section of artillery under his command to be dispatched to Ohio for the purpose of checking the raid of the Confederate general John Morgan, and aided materially in preventing the raiders from recrossing the Ohio River and in compelling Morgan to surrender. In the spring of 1864 commanded a brigade in General Crook's expedition to cut the principal lines of communication between Richmond and the Southwest. Distinguished himself by conspicuous bravery at the head of his brigade in storming a fortified position on the crest of Cloyd Mountain. Commanded a brigade in the first battle of Winchester. Took a creditable part in the engagement at Berryville, and at the second battle of Winchester, September 19, 1864, performed a feat of great bravery. Leading an assault upon a battery on an eminence, he found in his way a morass over 50 yards wide. Being at the head of his brigade, he plunged in first, and, his horse becoming mired at once, he dismounted and waded across alone under the enemy's fire. Signaled his men to come over, and when about 40 had joined him he rushed upon the battery and captured it after a hand-to-hand fight. At Fishers Hill, September 22, 1864, being then in command of a division, executed a brilliant flank movement over mountains and through woods, took many pieces of artillery, and routed the enemy. At the battle of Cedar Creek, October 19, 1864, his conduct attracted so much attention that his commander, General Crook, commended him, saying, "Colonel, from this day you will be a brigadier-general." The commission reached him a few days afterwards. March 13, 1865, received the rank of brevet major-general "for gallant and distinguished services during the campaign of 1864 in West Virginia, and particularly at the battles of Fishers Hill and Cedar Creek, Virginia." In August, 1864, while in the field, was nominated for Congress and elected. After the war, returned to civil life, and took his seat in Congress December 4, 1865. Voted with his party on questions connected with the reconstruction of the Southern States; supported a resolution declaring the sacredness of the public debt and denouncing repudiation, and also one commending President Johnson for declining to accept presents and condemning the practice; opposed a resolution favoring an increase of pay of members